1. Field of the Invention
This invention relates to the field of cutlery. More specifically, this invention relates to the art of helping persons having undeveloped, reduced, or impaired motor skills to feed themselves.
2. Background Art
Many people find it difficult to feed themselves with conventional cutlery due to their physical status. Young children may find it frustrating to try to emulate their parents' use of forks and spoons at the dinner table. More often, the parents of those children have found it taxing to endure the constant spillage of food while indoctrinating the youngsters in the proper use of the forks and spoons. Before the age of eighteen months, many children are still struggling to develop the physical coordination necessary to master adult-style eating habits.
Adults may also have trouble using common cutlery. Some diseases, such as cerebral palsy (CP) and Parkinson's, and injuries to the spinal column can result in partial impairment of motor skills which make feeding one's self difficult, if not impossible. Parkinson's and CP cause uncontrollable tremors in the arms which make it difficult to hold liquid on a spoon or to aim a fork at a given piece of food. Spinal column injuries (or other kinds of nerve damage for that matter) can result in an ability to only partially control the movement of the arms; the possible range of motion is likely limited and eye-to-hand coordination may be affected. Other people are challenged by conditions caused by severe arthritis or arm injuries which simply limit the useful range of motion of their arms.
So-called "self-leveling spoons" of various designs have been proposed to help people feed themselves without spilling food excessively. Although differing from one another in one aspect or another, the conventional self-leveling spoons share a common characteristic of having a single degree of rotational freedom which is about the longitudinal axis of the handle of the spoon. The following patent documents disclose spoons which adopt this conventional design:
U.S. Pat. No. 659,341; PA1 U.S. Pat. No. 2,636,266; PA1 U.S. Pat. No. 2,682,705; PA1 U.S. Pat. No. 2,741,027; PA1 U.S. Pat. No. 2,809,426; PA1 U.S. Pat. No. 4,028,803; PA1 U.S. Pat. No. 4,389,777; PA1 U.S. Pat. No. 4,993,156; PA1 British patent doc. no. 833,889 (May 4, 1960); PA1 German patent doc. no. 2,005,351 (Aug. 19, 1971).
It has been proposed to fasten a self-leveling spoon to the hand of the user with straps. U.S. Pat. No. 4,325,187 shows a self-leveling spoon which discloses a strap system for fastening the handle of the spoon to the user's hand. This is illustrated in FIG. 5 as element 12. As with other conventional self leveling spoons, the bowl 18 has only a single degree of rotational freedom with respect to the handle 20, 32, which is along the longitudinal axis of the handle.
The most salient limitation of the conventional self-leveling spoons is the ability to rotate about only one axis. These spoons will function adequately if the axis of rotation of the user's hand happens to coincide precisely with the longitudinal axis of the spoon. If the user fails to accomplish this coincidence, the spoon will spill its contents just like an ordinary spoon. For most persons with impaired or undeveloped physical capacities, this is simply too much to ask.
In the last decade, solutions of increasing sophistication have been proposed. U.S. Pat. No. 4,433,950 shows a motorized self-feeding apparatus which has a spoon B which is moved about by a complex mechanical linkage system (see FIGS. 1 & 3). U.S. Pat. No. 5,037,261 shows a motorized self-feeding apparatus which has a spoon 20 which is moved about by a complex mechanical linkage system. FIGS. 2 & 3 are most illustrative. U.S. Pat. No. 5,282,711 shows a robotic self-feeding apparatus which has a spoon 64 which is moved about by a complex mechanical linkage. The system is computer controlled. The devices proposed by these disclosures are of such a high level of complexity and sophistication that they would almost certainly cost at least two orders-of-magnitude more to manufacture than ordinary spoons.
Forks have been disclosed which have tine portions which rotate with respect to their handles. However, it does not appear that these would be particularly helpful to persons with impaired motor skills. These inventions are directed toward solving the particular problem of eating spaghetti. U.S. Pat. No. 2,602,996 shows a fork which a prong and shank section 14 which rotates with respect to the handle 13. Rotation is along the longitudinal axis of the handle and is controlled by the user at thumb wheel 15. U.S. Pat. No. 4,599,797 shows a fork which a prong and shank section 14 which rotates with respect to the handle 12. Rotation is along the longitudinal axis of the handle and is controlled by the user at thumb wheel 18.
A dipping device has been proposed which provides for rotation of a bowl with respect to the handle about more than one axis. U.S. Pat. No. 1,545,365 shows a skimmer ladle which has a bowl 4 which rotates with respect to the handle 5. It has two degrees of rotational freedom which are about the orthogonal axes which are transverse to the longitudinal axis of the handle of the ladle. Rotation of the bowl 4 is performed by the user manipulating controls 20, 15, 10, 12. The skimmer ladle has no self-leveling structure to prevent spilling.
A problem common to the conventional self-leveling spoons is the trapping of food particles inside the moving parts. Cleaning of the conventional spoons is difficult when food or dirt gets into the moving parts.